An excellent learning exercise for students of economics is to take a journal article that uses data to model the economy and then try to replicate the authors’ results. You may well be given an assignment like this in future years of your degree.
One such exercise is used on the University of Massachusetts Amherst’s doctoral programme in economics. Thomas Herndon is a student on that degree and chose to examine a well-known and highly influential paper, Growth in a Time of Debt by Carmen Reinhart then of the University of Maryland and Kenneth Rogoff of Harvard University and former chief economist of the IMF. Professors Reinhart and Rogoff used new data on 44 countries spanning about 200 years.

A key finding of their paper, published in 2010 in the American Economic Review Papers and Proceedings, is that once a country’s government debt exceeds 90% of GDP, growth rates fall considerably: the median across countries by about 1% and the mean considerably more.
The paper has been hugely influential. It has been used to justify the austerity programmes being pursued in many countries, including the UK and the eurozone. Cutting the government deficit to GDP ratio, and ultimately the government debt to GDP ratio, has been seen as a way of achieving higher growth over the longer term, and justifies the adverse effect on short-term growth from the dampening of aggregate demand.
Well, this seemed an interesting paper for Thomas Herndon to examine, and he was keen to show just how Reinhart and Rogoff’s data led to their conclusions. But try as he might, he could not replicate their results. His initial reaction was to think he had made an error, but each time he checked he came back with the same conclusion: they must have made errors in their calculations.
His supervisor at Amherst, Professor Michael Ash, after Thomas had checked and checked again, realised that something was wrong. He encouraged Thomas to write to Reinhart and Rogoff to request sight of their dataset. They duly obliged and it was then that Thomas spotted various errors. These are explained in the articles below, but the overall effect was to alter the conclusion. Although high debt may undermine growth to some extent, the effect is much less than Reinhart and Rogoff concluded, and there are several exceptions to this rule.
On 15 April 2013, Thomas, along with his supervisor, Michael Ash and his colleague, Robert Pollin, published a response to the Reinhart and Rogoff paper. In the abstract to their paper, Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogoff they state that:
… coding errors, selective exclusion of available data, and unconventional weighting of summary statistics lead to serious errors that inaccurately represent the relationship between public debt and GDP growth among 20 advanced economies in the post-war period. They find that when properly calculated, the average real GDP growth rate for countries carrying a public-debt-to-GDP ratio of over 90 percent is actually 2.2 percent, not –0:1 percent as published in Reinhart and Rogoff. That is, contrary to RR, average GDP growth at public debt/GDP ratios over 90 percent is not dramatically different than when debt/GDP ratios are lower.
The authors also show how the relationship between public debt and GDP growth varies significantly by time period and country. Overall, the evidence we review contradicts Reinhart and Rogoff’s claim to have identified an important stylized fact, that public debt loads greater than 90 percent of GDP consistently reduce GDP growth.
So could this be you in the future? Will you take a famous paper and, by re-examining and reworking the data, find that its conclusions are wrong? Could you end up changing the world? Exciting stuff!
Podcasts
Austerity: A Spreadsheet Error? BBC, More or Less, Tim Harford (20/4/13)
Austerity justification study ‘inaccurate’ BBC Today Programme, Robert Pollin (18/4/13)
Articles
UMass Student Exposes Serious Flaws in Harvard Economists’ Influential Study The Atlantic Wire, J.K. Trotter (18/4/13)
Shocking Paper Claims That Microsoft Excel Coding Error Is Behind The Reinhart-Rogoff Study On Debt Business Insider, Mike Konczal (16/4/13)
How a student took on eminent economists on debt issue – and won Economic Times of India (19/4/13)
Meet the 28-Year-Old Grad Student Who Just Shook the Global Austerity Movement New York Magazine, Kevin Roose (19/4/13)
An economist’s mea culpa: I relied on Reinhart and Rogoff Confessions of a Supply-Side Liberal blog, Miles Kimball (22/4/13)
The Rogoff-Reinhart data scandal reminds us economists aren’t gods The Guardian, Heidi Moore (18/4/13)
Reinhart, Rogoff… and Herndon: The student who caught out the profs BBC News Magazine, Ruth Alexander (20/4/13)
George Osborne’s case for austerity has just started to wobble The Guardian, Polly Toynbee (18/4/13)
The error that could subvert George Osborne’s austerity programme The Guardian, Charles Arthur and Phillip Inman (18/4/13)
The Excel depression Sydney Morning Herald, Paul Krugman (19/4/13)
Europe: Retreat from austerity BBC News, Gavin Hewitt (23/4/13)
Guest post by Thomas Herndon
The Grad Student Who Took Down Reinhart And Rogoff Explains Why They’re Fundamentally Wrong Business Insider, Thomas Herndon (22/4/13)
Papers
Growth in a Time of Debt NBER working paper, Carmen M. Reinhart and Kenneth S. Rogoff (January 2010)
Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogoff PERI Working Paper 322, Thomas Herndon, Michael Ash and Robert Pollin (April 2013)
Questions
- What were the particular errors made by Reinhart and Rogoff?
- How has their paper been used as a basis for the design of macroeconomic policy?
- What are the limitations of using even accurate time-series data as the basis for policy measures?
- How might the work of Herndon change the direction of future macroeconomic policy?
- In his guest post in Business Insider (see link above), Herndon wrote: ‘The implication for policy is that, under particular circumstances, public debt can play a key role in overcoming a recession.’ What might this role be?
- Why might we have to be cautious in drawing policy conclusions from Herndon’s work?
The market for any good or service is affected by countless factors. On the demand-side, things such as incomes, relative prices, expectations of price changes and tastes determine the shape and position of the demand curve. For the supply curve, it’s factors including costs of production, the profitability of alternative goods and in some cases, the weather or natural disasters. It is this last factor, which has presented Weetabix with problems.
An established breakfast cereal and brand, Weetabix is well-known for producing a range of high quality products. However, production of some of its most popular products has been stopped, as the quality of the British wheat used to make the various cereals was called into question. Last year, we had little summer to speak of and this led to the ‘worst harvest we have seen in decades’, so much so that the quality of the wheat was not sufficient to be used in making the breakfast cereal. This has caused production to cease on certain products and shortages have already begun to emerge, with some shops completely selling out and facing no prospect of being re-stocked.
Weetabix is now owned by a Chinese state-owned company, but still prides itself on using locally sourced wheat. However, with the weather affecting the harvest, wheat from abroad has had to be used, aiming to reduce the gap between demand and supply. The UK is typically an exporter of wheat, but with the poor harvest has come a drop in the amount of wheat produced and thus exported by some 2m tonnes – this is back to a similar level as was seen in the 1980s. A spokesman for Weetabix said:
Normally they’re proud to claim Weetabix is not just British wheat but from within 50 miles of Burton Latimer … They have had to source a bit from outside the UK, but Weetabix is still proud to say it sources its wheat within the UK … weather permitting.
Supply will be increased once wheat from abroad is used, but it is expected that this will take a couple of weeks. In the meantime, if you’re a consumer of the traditional Weetabix, you don’t need to worry, as it’s the less-known cereals that have been affected. The following articles consider this external factor and how it affects the supply of a product.
Weetabix products hit by poor wheat harvest BBC News (22/4/13)
Weetabix supplies hit by dismal harvest The Guardian, Rupert Neate (22/4/13)
Weetabix move to scale back production and re-engineer process is a commendable one The Grocer (20/4/13)
Britain’s disastrous wheat harvest halts production of Weatbix Minis and Oatibix Mail Online, Leon Watson (22/4/13)
Bad weather threatens wheat harvest Channel 4 News, Tom Clarke (3/4/13)
Weetabix halts production of Minis after poor harvest Farmers Weekly, Philip Case (22/4/13)
Questions
- With a poor harvest, which way would you expect the supply curve to shift? Illustrate this on a diagram.
- How should this shift in supply affect the market price and quantity of wheat, assuming all else remains the same?
- How can this example can be used to explain the interdependence between markets?
- With shortages possibly emerging, what might happen to demand today? Illustrate your answer on a demand and supply diagram.
- Does sourcing wheat from local areas give Weetabix a competitive advantage? If so, how might it be affected if it does choose to import wheat?
Unemployment is a key macroeconomic objective for governments across the world. The unemployment rate for the UK now stands at 7.9% according to the ONS, which recorded 2.56 million people out of work. But why is unemployment of such importance? What are the costs?
The economy is already in a vulnerable state and with unemployment rising by 70,000 people between December and February 2013, the state of the economic recovery has been questioned. Indeed, following the news of the worsening unemployment data, the pound fell significantly against the dollar, suggesting a lack of confidence in the British economy.
Although the increase in the number of people out of work is concerning, perhaps of more concern should be the number of long-term unemployed. The ONS suggests that more than 900,000 have now been out of work for more than a year. Not only does this pose costs for the individual in terms of lost earnings and skills, but it also imposes costs on friends and family and the wider economy. (Click here for a PowerPoint of the first chart, which shows the percentage of unemployed people out for work longer than 12 months.)
The chief executive of the Prince’s Trust focused on the costs of youth unemployment in particular, saying:
Thousands of these young people are long-term unemployed, often facing further challenges such as poverty and homelessness. We must act now to support these young people into work and give them the chance of a better future.
(Click here for a PowerPoint of the second chart, which shows how much higher the unemployment rate is for young people aged 18 to 24 than it is for the working age population as a whole.)
Furthermore, with so many people unemployed, we are operating below full-employment and thus below our potential output. Furthermore, the longer people are out of work, the more likely it is that they will lose their skills and thus require re-training in the future or find that there are now fewer jobs available to them based on their lower skill level.
In addition to this there are monetary costs for the government through lower tax receipts, in terms of income tax, national insurance contributions and even VAT receipts. With more people unemployed, the numbers claiming various unemployment-related benefits will rise, thus imposing a further cost on the government and the taxpayer. Another cost to the government of this latest data is likely to be the expectations of the future course of the economy. Numerous factors affect business confidence and unemployment data is certainly one of them. The concern is that business confidence affects many other variables as well and until we receive more positive data, the economy recovery is likely to remain uncertain. The following articles consider this topic.
UK unemployment rise adds to pressure on Osborne’s austerity strategy The Guardian, Phillip Inman (18/4/13)
Unemployment figures are ‘worrying’, David Cameron’s spokesman says The Telegraph, Peter Dominiczak (17/4/13)
UK unemployment rises to 2.56 million BBC News (17/4/13)
Unemployment jumps to 7.9% as rise in the number of young people out of work takes figure ‘dangerously’ close to a million Mail Online, Leon Watson (17/4/13)
Unemployment up as stay-at-home mothers head back to the job-centre Independent, Ben Chu (17/4/13)
Jobs data points to finely balanced market Financial Times, Brian Groom (18/4/13)
Hugh’s review: making sense of the stats BBC News (19/4/13)
Questions
- How is unemployment measured?
- What are the costs to the individual of being unemployed?
- What are the wider non-monetary costs to society?
- Explain the main financial costs to the wider economy of a rising unemployment rate.
- Illustrate the problem of unemployment by using a production possibility frontier.
- Could there be a negative multiplier effect from a rise in unemployment?
On 5 and 6 April, there was a conference on conscious capitalism in San Francisco. In January, a new book, Conscious Capitalism: Liberating the Heroic Spirit of Business, by John Mackey and Rajendra Sisodia, was published. Many in the business world are enthusiastic about this seemingly new approach to business, which focuses on broader social, environmental and ethical goals, rather than simple profit maximisation.
As the Washington Times review linked to below states:
“Conscious Capitalism” promotes a business culture that embodies “trust, accountability, caring, transparency, integrity, loyalty and egalitarianism.” The management ideal of “Conscious Capitalism” contains four key elements of “decentralization, empowerment, innovation and collaboration.” Above all, this exemplary form of business practice relies on careful attention to four tenets: higher purpose and core values, stakeholder integration, conscious leadership and conscious culture and management.
So how realistic is this vision of caring capitalism? There may be a few inspiring businesspeople, truly committed to improving the interests of the various stakeholders of their business and society more generally, but could it become a model for business in general? And if so, does this require education, monitoring and regulation? Or can a libertarian approach to business generate an environment where conscious and caring capitalists flourish and succeed better than those with a more narrow focus on profit?
The following videos and articles discuss conscious capitalism and the arguments of those, such as John Mackey, founder and co-CEO of Whole Food Market, who advocate it.
Webcasts
Conscious capitalism The Economist, John Mackey (15/3/13)
Conscious Capitalism: Heroes of the Business World Conscious capitalism, April in San Francisco (5/4/13)
It’s Not Corporate Social Responsibility Conscious capitalism, John Mackey (Jan 13)
Articles, reviews and information
Conscious Capitalism: Creating a New Paradigm for Business Whole Planet Foundation, John Mackey
Companies that Practice “Conscious Capitalism” Perform 10x Better Harvard Business Review, Tony Schwartz (4/4/13)
4 Ways to Become a (More) Conscious Capitalist Inc., Francesca Louise Fenzi (8/4/13)
The New Management Paradigm & John Mackey’s Whole Foods Forbes, Steve Denning (5/1/13)
Book Review: ‘Conscious Capitalism’ Washington Times, Anthony j. Sadar (20/3/13)
Book Review: Whole Foods Co-CEO John Mackey’s Conscious Capitalism Huffington Post, Christine Bader (28/1/13)
Chicken Soup for a Davos Soul Wall Street Journal, Alan Murray (16/1/13)
Conscious business Wikipedia
Questions
- What are the features of conscious capitalism?
- Do firms “get the shareholders they deserve”?
- How might firms that are not pursuing conscious capitalism be persuaded to become more conscious and more caring?
- How does conscious capitalism differ from corporate social responsibility?
- What would you understand by “conscious consumers”? How might their behaviour differ from other consumers?
- Why might firms engaging in conscious capitalism become more profitable than firms that have a simple aim of profit maximisation?
- What reforms, both internal within a firm and in the legal environment, does John Mackey advocate? Do you agree with his suggestions? What else do you suggest?
When you hear about China, it’s often regarding their huge population, their strong growth or their dominance in exports. But, when it comes to baby milk, China is certainly an importer – and a big one at that. For many new parents, getting the ‘real thing’ when it comes to baby formula is absolutely essential.
Chinese baby formula is feared by many new parents, due to the potential for it to contain hormones and dangerous chemicals. This has led them to go to great lengths to ensure they have sufficient supplies of imported baby formula, often only trusting it if it has been hand carried from overseas. However, such is the demand for this safe version of baby milk that the global response has been to place restrictions on it. Essentially, we are seeing a system of rationing emerging.

Hong Kong was the first government to limit the amount bought to two cans of formula per day, with the potential for a fine of over $64,000 and up to two years in prison for those who do not abide by the rules. The UK has now also responded with restrictions on the quantity that can be purchased and other countries may follow suit if the excess demand continues.
According to Sainsburys:
As a short-term measure, retailers including Sainsbury’s are limiting the amount of baby milk powder that people can buy. In this way we aim to ensure a constant supply for our customers and we therefore hope they won’t be inconvenienced.
The Chinese government has reacted to this and is aiming to restore confidence in the food industry, but as yet there has been little positive effect and until there are 100% guarantees of food safety the surge in demand for baby formula from abroad is likely to continue.
This policy of rationing is clearly not only going to affect Chinese parents looking to import baby formula, but is already having an impact on domestic residents. Parents living in the UK are feeling the rationing effects and are also being restricted in terms of how many cans of formula they can buy per day. For many families this isn’t a problem, but for those with multiple children and for whom a trip to the supermarket is not a simple task, the restrictions on baby milk purchases is likely to become a problem. The following articles consider this topic.
Baby milk rationing: Chinese fears spark global restrictions BBC News, Celia Hatton (10/4/13)
Stop rationing information about baby formula milk The Telegraph, Rosie Murray-West (9/4/13)
Baby milk rationed in UK over China export fear BBC News (8/4/13)
Baby Formula rationed in UK over China demand Sky News (9/4/13)
Supermarkets limit sales of baby milk to stop bulk buying to feed China market Independent, Emma Bamford (8/4/13)
Cahinese thirst for formula spurs rationing Financial Times, Amie Tsang and Louise Lucas (7/4/13)
Entrepreneurs milk Chinese thirst for formula Financial Times, Amie Tsang and Louise Lucas (7/4/13)
Baby milk powder rationing introduced by supermarkets The Guardian, Rebecca Smithers (8/4/13)
Questions
- Using a diagram of demand and supply, illustrate how a shortage for a product can emerge. How does the price mechanism usually work to eliminate a shortage?
- What actions can be taken to deal with a shortage?
- How will more stringent regulations by the Chinese government help to restore confidence in Chinese baby milk formula?
- What impact will the imports of baby milk formula into China have on China’s exchange rate and its balance of payments?
- How could this situation be taken advantage of by entrepreneurs? Could it be used as a viable business opportunity?